Fastrock, Cast Stone or Calmix 801 is a cement mortar with special additives and is suitable for quick casting of sculptures. Widely used in restoration and renovation projects, but is also suitable for serial industrial use. Properties: Maximum grain size: 1.0 mm. Can be coloured with pigment (add maximum 5%). Recommended mixing ratio 0.42 kg water to 2.5 kg dry matter. Or 1.68 kg water to 10 kg dry matter.